<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .box {
            width: 300px;
            height: 300px;
            margin: 0 auto;
            background-image: conic-gradient(from 0deg at center ,red 0 120deg, green 120deg 240deg, blue 240deg 360deg);
            /* 
                原点：位置 同 background-position
                起始角度：from + 角度
            */
            border-radius: 50%;
        }
        .box1 {
            width: 400px;
            height: 400px;
            margin: 0 auto;
            background-size: 40px 40px;
            /* background-repeat: no-repeat; */
            background-image: conic-gradient(#fff 0 90deg, #000 90deg 180deg, #fff 180deg 270deg, #000 270deg 360deg);
        }
        .box2 {
            width: 400px;
            height: 400px;
            margin: 0 auto;
            border-radius: 50%;
            background-image: conic-gradient(#f00,#ff0, #0f0,#0ff, #00f, #f00);
        }


    </style>
</head>
<body>
    <div class="box"></div>
    <div class="box1"></div>
    <div class="box2"></div>
</body>
</html>
